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Revised Cross-State Air Pollution Rule Update

Final Rulemaking

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Rule Summary

On March 15, 2021, EPA finalized the Revised Cross-State Air Pollution Rule Update for the 2008 ozone National Ambient Air Quality Standards (NAAQS). Starting in the 2021 ozone season, the rule will require additional emissions reductions of nitrogen oxides (NOX) from power plants in 12 states, improving air quality for millions of Americans.

EPA estimates that the Revised CSAPR Update will reduce NOX emissions from power plants in 12 states in the eastern United States by 17,000 tons in 2021 compared to projections without the rule, yielding public health and climate benefits that are valued, on average, at up to $2.8 billion each year from 2021 to 2040.  

Cross-State Air Pollution Rule RegionsCross-State Air Pollution Rule Regions

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Rule History

March 15, 2021 - Final Revised Cross-State Air Pollution Rule Update

EPA is issuing new or amended Federal Implementation Plans (FIPs) in 12 states to address air quality impacts of the interstate transport of ozone air pollution in the eastern United States. The final rule was published in the Federal Register on April 30, 2021.

Technical Support Documents (TSDs)

Additional supporting information and data for the listed TSDs are available in the official docket.

Previous Actions - Proposed Rulemaking

October 15, 2020 - Proposed Revised Cross-State Air Pollution Rule Update

EPA proposed to issue new or amended Federal Implementation Plans (FIPs) to revise emission budgets in 12 states to address air quality impacts of the interstate transport of ozone air pollution.

Technical Support Documents (TSDs)

Additional supporting information and data for the listed TSDs are available in the official docket.

Additional Resources

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